Hiding files and folders from the Finder:

chflags hidden filename

And show them again:

chflags nohidden filename

Check whether a folder exists, otherwise create it.

NSFileManager *fm = [NSFileManager defaultManager];
 
if (![fm fileExistsAtPath:myPath isDirectory:NULL]) {
		[fm createDirectoryAtPath:myPath withIntermediateDirectories:NO attributes:nil error:nil];
}

OSX 10.6.2

diskutil erasevolume HFS+ “ramdisk” `hdiutil attach -nomount ram://1000000`

Would create a 500MB RAM Disk. The size is calculated in 512K Block, 512K * 1000000 = 500MB

Works nicely.

From here.

- – -

However, if you want to mount the RAM Disk at a specific point in your filesystem, the method above does not seem to work.

Instead try:

hdiutil attach -nomount ram://10000
Create, attach but do not mount our RAM Disk (returned /dev/disk2)

newfs_hfs -v Ramdisk /dev/disk2
Name and format the disk

mount -t hfs /dev/disk2 /your/path/
Mount the disk at a specific point. The address has to be absolute, and should point to an empty folder. Once mounted, the folder gets replaced by the RAM Disk.

umount /dev/disk2
Unmounting by ejecting the disk does not seem to work…

Sources: - - - - -